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08dbd0f8ef
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 and only version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 51 franklin street fifth floor boston ma 02110 1301 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 94 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190529141334.043630402@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
88 lines
1.9 KiB
C
88 lines
1.9 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* vDSO implementation for Hexagon
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*
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* Copyright (c) 2011, The Linux Foundation. All rights reserved.
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*/
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#include <linux/err.h>
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#include <linux/mm.h>
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#include <linux/vmalloc.h>
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#include <linux/binfmts.h>
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#include <asm/vdso.h>
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static struct page *vdso_page;
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/* Create a vDSO page holding the signal trampoline.
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* We want this for a non-executable stack.
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*/
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static int __init vdso_init(void)
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{
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struct hexagon_vdso *vdso;
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vdso_page = alloc_page(GFP_KERNEL);
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if (!vdso_page)
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panic("Cannot allocate vdso");
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vdso = vmap(&vdso_page, 1, 0, PAGE_KERNEL);
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if (!vdso)
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panic("Cannot map vdso");
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clear_page(vdso);
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/* Install the signal trampoline; currently looks like this:
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* r6 = #__NR_rt_sigreturn;
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* trap0(#1);
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*/
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vdso->rt_signal_trampoline[0] = __rt_sigtramp_template[0];
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vdso->rt_signal_trampoline[1] = __rt_sigtramp_template[1];
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vunmap(vdso);
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return 0;
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}
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arch_initcall(vdso_init);
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/*
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* Called from binfmt_elf. Create a VMA for the vDSO page.
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*/
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int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
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{
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int ret;
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unsigned long vdso_base;
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struct mm_struct *mm = current->mm;
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if (down_write_killable(&mm->mmap_sem))
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return -EINTR;
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/* Try to get it loaded right near ld.so/glibc. */
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vdso_base = STACK_TOP;
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vdso_base = get_unmapped_area(NULL, vdso_base, PAGE_SIZE, 0, 0);
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if (IS_ERR_VALUE(vdso_base)) {
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ret = vdso_base;
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goto up_fail;
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}
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/* MAYWRITE to allow gdb to COW and set breakpoints. */
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ret = install_special_mapping(mm, vdso_base, PAGE_SIZE,
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VM_READ|VM_EXEC|
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VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
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&vdso_page);
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if (ret)
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goto up_fail;
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mm->context.vdso = (void *)vdso_base;
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up_fail:
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up_write(&mm->mmap_sem);
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return ret;
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}
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const char *arch_vma_name(struct vm_area_struct *vma)
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{
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if (vma->vm_mm && vma->vm_start == (long)vma->vm_mm->context.vdso)
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return "[vdso]";
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return NULL;
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}
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